Fuel supply system



P. l, scorT 2,046,491

FUEL SUPPLY SYSTEM July-7, 1936.

Original Filed 'OGL 20, 1950 f# ffff f2 @f 3 ZH, @I Wwf a@ -Y//l/ if# si j f2 W`7ZV ucm; i2 n f6 [n ver? for Patented July 7, 1936 UNITED STATES FUEL SUPPLY SYSTEM Philip Lane Scott, Chicago, Ill., assignor to Super Diesel Tractor Corporation, La Porte, Ind., a corporationeof New York Reiiled i'or abandoned application Serial No. A 489,749, October 20, 1930. This application March 13, 1933, Serial No. 660,526

27 Claims. (Cl. ICB- 152) This invention relates to a iluidsupply and pumping system. This application is a substitute for my application Serial No. 489,749, filed October 20. 1930. In one embodiment it has for one object to provide means for pumping fluid and to provide means for actuating the fuel pump without the use of a mechanical linkage.

Another object is to provide in connection with a fuel pump a hydraulic means for' actuating the same.

Another object is to provide a fuel pump capable of discharging fuel at extremely high pressures. A still further object is to provide a fluid pump capable of discharging relatively small quantities of uid athigh pressures and at great speed.

Other objects will appear from time to time in the specification and claims.

My invention is illustrated more or less dlagrammatically in the accompanying drawing, wheleln Figure 1 is a section through the fuel supply system;

Figure 2 is a transverse detailed cross section taken at line 2--2 of Figure 1.

Like characters illustrate like parts throughout the specification and drawing.

A is a base of any suitable sort to which the actuator may be fastened. It might, for example, be a portion of an engine with which the actuator isdesigned to operate to'furnish fuel.

B is a portion of the actuator base which may be fastenedto the support A by screws Bx or by any yother suitable means. The base B has an upwardly projecting hollow portion Bl which is provided with a laterally extending ange B. An actuator housing B* is provided with an enlargement B. having a flange B' which may be placed in contact with the -ilsnge Ba andfastened to.

it by screws BI or by any other suitable means'.

The member B* is provided with l. bore B' and is preferably provided with an enlarged head portion B. At; its upper end the bore B' is enlarged. and interiorly threaded'as 'st Blhj llhe .heed portion B of the actuator housing is providedr with an inlet and outlet passage B,u which may be enlarged and interiorly thresded'ss let B1.-

The passage Bn communicates with s passage B11 which lesdsto an annular passage or enportion B1'. From the valve cageB" a passage B19 leads to the upper end of the bore BB. B20 is a ball check valve positioned within the intake line and adapted to be Vopened by suction within the actuator and seated by pressure within the actuator and by the spring shown. B2l is a bypass 'passage leading from the upper end of the actuator bore Ba to a passage B22 which leads into the passage B11. The by-pass valve B23 is adapted to be seated in the passage B21. It is provided with a threaded portion B24 and a levev arm. B, to which a link or connection B may.A

be fastened.

C is a plug seated in and closing the passage B, Cl is a plunger or piston mounted' and adapted to move within the bore'B8 of the actuator. At its upper end it is provided with a perforation or hollowed out portion C2. C3 is `a perforation or cut away portion preferably adjacent the upper end of the piston C1 and communicating with the perforation or bore C2. At its lower end the piston Cl carries the enlargement C*. C5 is a spring bearing at one end upon the housing B* and at the other end upon the e largement C4. C* is a shaft driven in phase wth an, engine to which the system is applied, and carrying a cam C". The cam contacts the enlargement C* and movesthe piston during its rotation.'

D is a connection seated in the passage B, serving to connectthe by-pass or supply conduit Dl to the cylinder and to a supply tank. notA shown.

E is a connection positioned in the passage Blo and serving Ito*l connect a supply conduit lill to the pump cylinder. At its other end the conduit -lll is connec to an injector unit by 'a connection Ewhich is ls Lted in a seating or connecting Portion Eywhilcy itself positioned upon 4the injector unit.

The injector unltincludesan actuating tube F. which may or may not be made with enlarged ends F1. IN. The `tubeli' is preferably of oval cross section.' as indicated in'Flgure 2, and the enlarged ends may be rounded. The rounded ends, whilejnot essentiaL'are usually simpler for connection to the other parts with which the tube is associated. The end Fl is preferably mounted non e reduced part IN of a housing member Ft This member is hollow, as'shown. and the tube may be welded or. otherwise secured upon its reduced'portion I". At its outer end the member F* may be interiorly threaded as at F5. At its opposite end .the p'ortlon F1 of the tube F ls iastened within a housing part-F'. This part is interiorly threaded as at F to receive the correspondingly threaded portion of the actuating tube and is provided with a reduced extension F* which may be interiorly tapered as at F and exteriorly threaded as at FW.

Within the tube F is mounted a second or pump tube G. This tube is preferably more or less oval in cross section as indicated particularly in Figure 2, and may be positioned so that its major axis corresponds generally with the minor axis of the actuating tube F. For convenience in .attachment and connection the tube G may be rounded at its ends as at G1, G2. The end G1 is positioned within and secured to the member F'. The end G2 is positioned within andsecured to the extension Fa of theimember Fi. For-con venience the ends G1l G2 may be flared outwardly as indicated in Figure 1; Both of the tubes F and G may be fastened to their supporting parts in any suitable manner. In the drawing they are indicated as being.welded or screwed into place or both. Either of th'ese methods of attachment may be used separately or together or any other suitable meansv may be used. G3. G1i are compression members positioned within the actuating tube F as indicated indetail in Figure 2, and having their outer ends generally curved as at G4 and-,bearing against the inner walls of the actuating tube. *Their inner ends are more nearly fiat as at G5 and are positioned to bear against the relatively flattened sides of the pump tube G.

H is an inlet valve housing exteriorly threaded as at Hl and screwed into place in the' member F4 engaging the threads F5. It is provided with an interior bore or hollow H2, to which a passage H3 leads.. The passage H3 is positioned preferably in a reduced exteriorly threaded extension H4, to which a supply pipe or conduit H leads. This conduit is held in position on the. extension H4 by a membe H. Within the portion H of the valve housing H 's positioned a valve member H". which preferably has the enlarged end H', which is adapted to be seated in a valve seat H formed on the inner end of the valve housing H. A spring H1 tends nonnally to hold the valve seated.

Positioned on the exteriorly threaded portion Fs and engaging the threaded part FW is an in- Jection valve housing I. This member is provided with a hollow exteriorlythreaded extension I1 and a'partition portion P may partially close the passage through the housing member I and the extension Il. 'I'hls partition member is provided with a perforation I. Positioned within the extension Il is a cage'I carrying a needle point or valve closing member I. The cage portion I* is provided with an extended and preferably annular portion I' against which a valve disc I1 is positioned. This disc may be 'formed of iaminations as shown, or might be made of a single member. It is provided with a perforation P and may have a removable seat plus p0rtion I. seated in the perforation Il and adapted to receive the needle point I. I". is a retaining cap member threaded upon the extension Il. engagingandlupportingthsvalvedisoandserving to hold the member I* in position. This cap thus holds the entire injection valve assembly in place.

Itwillberealisedthatwhereaslhaveherewith shown and described a, practical operative device,.nevertheiess many changes might be made in the size. shape. number and disposition of parts without departing from the spirit of my invention and I wish. therefore, that my showing betakonasinasensediagrammatic Thec'oinliquid and the liquid column surrounds th-e pump tube G within the actuating tube F. To illustrate one form of the operation of the device. it will be assumed that the system as a whole is mounted with an internal-combustion engine and is designed to furnish fuel to such an engine. The actuator unit may be mounted at any suitable part on the engine or in some cases on the vehicle upon which the engine is mounted. The injector or pump unit is mounted so that it will discharge fuel into an engine cylinder. The shaft C is driven in phase with the engine. Assuming now that the plunger or piston C1 is at the lower limit of its movement, its upper end isvbelow the annular portion B and thus the passages i312i and B are uncovered. As the shaft Ca rotates the cam C" is moved so as to force the piston C1 upward. As soon as it has moved upwardly a sufcient amount to pass beyond the annulus B14, the passages Bu and B are closed and if the valve B is fully seated there is no outlet for the :duid and there thus remains a solid fluid column extending from the top of the piston C1 to the pump tube G. As the movement of the cam continues, the piston is forced further upward. The liquid column is forced upwardv and the fluid which is for all practical purposes incompressible, is forced into the actuating tube F and tends to move it so as to increase its minor axis.

When this takes place its maior axis is reduced and the compression blocks GJ are forced against the pump tube G and bearing against its relatively ilat sides force them towards each other, thus reducing thevolume of the tube G and increasing the pressure within it. As pressure is thus developed within thepump tube G, the valve H' is held firmly on its seat and when the pressure increases sumciently the yielding portion of the injection valve. normally the disc I7, is forced outwardly. The amount` of movement of the disc I" is ordinarily minute and not sufficient to move the disc or the seat portion of the disc more than minutely away from the needle. the point of which still penetrates within the opening in the disc. A minute atomizing orifice is thus formed between the needle and the edges of the perforation or .opening through the disc and fuel is discharged through this opening.

As the movement of .the piston C1 still continues upwardly, the opening or perforation C1' which4 communicates with the hollow portion C2 of the piiton. comes into ro'giste-` lwith the annulus Bl and fluid may then escape through C. C! and into the annuius BN.' Thus during a per# tion of the movement of the piston, an escape is provided for the iluid above the piston, pressure is relieved, the actuating tube moves to its original position, the pump tube G is permitted to regain its original'position. pressure within the tube G is reduced. the valve disc resumes its original position, closing the`discharge opening and terminating discharge from the valve. The pump tube G expands of its own elasticity sufficiently to create suction within itself. which mseats the valve E;s and fuel is thus drawn into he Dump tube ready for the next discharge, or Vnl`ection stroke.

In the operation above described, it is stated that the valve B23 is seated and thus no liquid sgi escape through the passage B21 past the valve 13 This is the condition which would prevail inder full load. Under less than full load, the

gation to the movement of the engine controlling mechanism.

gf The conventional mechanically driven pumps .nd mechanically operated valve:` have been largely incapable of rapid motion under heavy jcad, due to the mere size.' shape and Weight of '.larts, superimposed as resistances upon the oil pressures to be developed. A successful injection system for an engine to operate at, say 2000 P. M. on a two-stroke cycle engine will re- ;guire 2000 pulsations inan oil column accomr'lanicd by delivery of some fuel at each pulsaion. The pressure may be built up from zero o a high pressure, say 5000 pounds or above, per gfquare inch for each pulsation. The quantity vf fuel delivered is relatively a very small amount Si each pulsation but it must be completely eject- 'yd in about .O01 of a second and not only must omplete ejection take place in this time but he pressure must rise to a maximum almost at f. rice, perhaps as quickly as .0001 of a second. g'hety'pe of pump of this application makes poslglble this extremely rapid building up of very Sigh pressures in very small fractions of a secnd, while the plunger pumps fail at far lower -Lpeeds and pressures.

l.lay be likened to the building up of electric "ressures in an'electric ignition system. In such system electric pressure must be built up from Yero to 10,000 volts in an extremely minute frac- ;icn of a second. 'Ihe break down of the dielectric between the electrodes occurs when. the pre- Aetermined voltage is reached, just as the ilexigle wall of my atomizing nozzle suddenly yields J'hen a predetermined pressure is reached. The 'lectric spark then discharges over an apprecible time interval just as the oil is discharged 'ver an appreciable but very short time interval. A design which is'to reduce the inertia forces ubstantially must have vmore regard for the' 'aceleration of the parts than for the mere reduclon of weight, since the inertia force is proortional to the square of the speed and only .irectly to the weight. If the length of the pay be moved can then be very materially reuccd, the-inertia forces will be reduced as the uaresof the speeds. Bimultaneously'with this eduction in length of travel of the-moving parts here is also an opportunity to reducethe weight f the parts, which then reduces theinertia force direct proportion. The total reduction so obined may prove a very substantial -ngure, for mple, considering the requirements of a 50 P. cylinder and a speed of 2000 R.. P, M., the nvenient size of the plunger for the convenonal plunger pump would be li of an inch in The action of the pump of this application.

troke or the distance through which the parts diameter by stroke. The moving parts associated with this plunger may weigh well over 1 pound, since this plunger must carry a load of 550 pounds to develop a pressure of 5000 pounds per square inch upon the fuel. If the length of travel of the moving parts could be reduced from of an inch to .015 inch, the inertia will be reduced to 1.3 per cent of the preceding value. If a flexible Wall weighing an ounce or less is substituted for a plunger and associated slider and roller, the weight of the parts may be cut to 6 or 7 per cent. The total reduction is such that the inertia forces will then be reduced to .09 per cent of their former figure.

In, the invention herewith described, the difflcult problem of reducing inertia forces to a point where a definite plus value of force available to produce pressure is achieved is met by reducing the travel of the elements actually producing the pressure on the fuel to an extremely minute amount or distance. These elements are. in the form shown. the fuel containing tube G (see Fig. 2) and the spacer pieces G3 which transmit the compressive force from the tube F to the tube G.

As metallic members these elements have substantial weight but their travel is very minute, normally being approximately .005 inch. T'he result of this is that the negative inertia of the parts available against the driving force is so slight as to be for practical purposes substantially negligible.

When these figures are considered in connection with the formula generally utilized for calculating the inertia force necessary to move a given part a given distance in a given time. the important and vital relationship ybetween the weight of the part and the distance it is to be moved and the bearing these factors have on the actual force necessary to be provided in a given case. is at once apparent. Thus,

wherein W is the weight of the part in pounds, S is the distance the part is moved in feet, and

T is the time in seconds during which the part is moved. By utilizing a pumping chamber including a deformable metal wall, constrained to a are merely representative and are cited for the purpose of providing comparison with .values obtaining in a pump made inl accordance with this invention' and similar values inpumps made in accordance with prior art practice. It is well within the range of possibility 'to make a pump in accordance with thel teachings of this invention which willI deliver fuel under pressure of five thousand pounds per square inch with the pump operating at two thousand strokes per minute. wherein the forces necessary to overcome inertia of the moving parts are relatively small in comparison with the forces necessary to sustain hydrostatic load on the pump. and with the pump operating at substantially one thousand strokes per minute and developing pressures of five hundred to one thousand pounds per square inch, the forces necessary to overcome the inertia of the moving parts may be kept well below the forces necessary to overcome the hydrostatic' load on the pump.

I claim:

1. In a hydraulically driven pump. a hollow actuating member and a hollow pumping member, inlet and outlet means for said pumping member, compression parts positioned to be moved by movement of said actuating member and to move said pumping tube, and means for iilling said actuating member with fluid and for acting upon said member hydraulically to cause the same to change its shape and volume and to move the compression members to act upon the pumping member to change its shape and volume. 2. In a differential hydraulically driven pump. a hollow flexible actuating member anda hollow iiexible pumping member, inlet and outlet means for said pumping member, compression parts positioned to be moved by movement of said actuating member and to move said pumping tube, and means for filling said actuating member with iiuid and for acting upon said member hydraulically to cause the same to change its shape and'volume and to move the compression members to act upon the pumping member to change its shape and volume.

3. In a hydraulically driven pump, a hollow actuating member and a hollow pumping member. inlet and outlet means for said pumping member, compression parts positioned to be moved by movement of said actuating member and to move said pumping tube, and means for filling said actuating member with fluid and for acting upon said member hydraulically to cause the same to change its shape and volume and to move the compression members to act upon,the pumping member to change its shape and volume, the actuating member being capable of returning of itself to its original form when free to do so.

4. In a hydraulically driven pump, a hollow actuating member and a hollow pumping member, inlet and outlet means for said. pumping member, compression parts positioned to be moved by movement of said actuating member and to move said pumping tube, and means for iilllng said actuating member with fluid and for acting upon said memberhydraulically to cause the same to change its shape and volume and to move the compression members to act'upon the pumping member to change its shape and volume, the pumping member being capable of returning of itself to its original'forrn when free to do so.

5. Ina hydraulically driven pump, a hollow actuating member and a hollow pumping member, inlet and outlet means for said pumping member, compression` parts positioned to be moved by movement -of said actuating member.

' and to move said pumping tube, and means for ililing said actuating member with fluid and for acting upon 'said' member hydraulically tocause the same to change its shape and mglume and to move the compression membersl act upon the pumping member to change its-shape and volume, the actuating member and the pumping member each being capable of returning of itself to its original form when free to do so.

6. In a hydraulically driven pump, a hollow flexible actuating tubular member-.and a hollow flexible pumping member, inlet and outlet means for said pumping member, compression parts positioned to be moved by movement of si actuating member and to move said pumpi tube. and means for iilling said actuating me: ber with fluid and for acting upon said meml hydraulically to cause the same to change shape and volume. and to move the compressi members to act upon the pumping member change its shape and volume.

7. In a hydraulically driven pump, a holl actuating member and a hollow tubular pumpi member, inlet and outlet means for said pumpi member, compression parts positioned to moved by movement of said actuating meml and to move said pumping tube, and means I iilling said actuating member with fluid and acting upon said member hydraulically to cai the same to change its shape and volume, and move the compression members to act upon 1 pumping member, to change its shape a volume.`

8. In a hydraulically driven pump, a holl actuating flexible tubular member and a holl flexible tubular pumping member, inlet and o1 let means for said pumping member, compress! parts positioned to be moved by movement said actuating member and to move said pun ins. tube, and means for filling said actuati member with fluid and for acting upon said me ber hydraulically to cause the same to cha: its shape and volume and to move the compress' members to act upon the pumping member change its shape and volume.

9. In a hydraulically driven pump, a hollow i tuating tubular member and a hollow pumpi member, inlet and outlet means for said pumpi member, compression'parts positioned to be moi by movement of said actuating member and move said pumping tube,and means for filli raid actuating member with iluid and for acti upon said member hydraulically. to cause 1 same to change its shape and volume, and to'ms the compression members to act upon the pun ing member to change its shape' and volume, i actuating member being capable of-returning itself to its original form when free to do so.

10. In a hydraulically driven pump, a holl actuating member and a hollow tubular pumpi member, inlet and outlet means for said pumpi member, compression parts positioned to be moi by movement of said actuating member and move said pumping tube, and means for iilli said actuating member with fluid and for acti upon said member hydraulically to cause the sa: to change its shape and volume, and toy move i compression members to act upon the pumpi member to change its shape and volume, i pumping member being capable of returning itself to its original form when free to do so.

1 1. In a hydraulically driven pump. a hoil actuating'tubular member and a hollow tubu' pumping member, inlet and outlet means for si pumping member.' compression parts positioned be moved by movement of said actuating me;

ber and to move said pmnping tube, and meeI for mung mdactuaung memberwith fluid af for acting upon said member hydraulically cause the same to change its shape and volus and to move thecompression members to i upon the `pumping member to change its sha' and volume, the actuating member and the purr; ing member each being capableof returning. itself to its original form when free to do so. l

12. In a hydraulically driven pump, a boli| actuating member and a hollow pumping membl inlet and outlet means for said pumping memb' compression parts positioned to be moved kv movement of said actuating member and to move i said pumping tube, said parts being within the j actuating member, and means for filling said y actuating member with tluid and for acting upon said member hydraulically to cause the same to change its shape and volume. and to move the compression members to act upon the pumping member to change its shape and volume.

i3. In a hydraulically driven pump, a hollow actuating member and a hollow pumping member. .Y within said actuating member. inlet and outlet means for said pumping member, compression parts positioned within said actuating member to j be moved by movement of said actuating member and to move said pumping tube, and means for filling said actuating member with fluid and for z acting upon said member hydraulically to cause the same to change its shape and volume and to move the compression members to act upon the pumping member to change its shape and volume.

14. In a hydraulically driven pump, a hollow actuating member and a hollow pumping member. within said actuating member, inlet and outlet means for said pumping member, compression shape and volume.

l5. In a diii'erential hydraulically driven pump. a hollow actuating member and a hollow pumping member within said actuating member, inlet and outlet means for said pumping member, compression parts positioned to be moved by movement oi' t said actuating member and to move said pumping tube, said parts being within the actuating member, and means for filling said actuating 2 member with fluid and for acting upon said memf ber hydraulically to cause the same to change its shape and volume, and to move the compression members to act upon the pumping member, to change its shape and volume.

16. In a hydraulically driven pump, a hollow actuating member and a hollow pumping member within said actuating member, inlet and outlet means for said pumping member, compression parts positioned to be moved by movement of said actuating member and to move said pumping tube, said parts being within the 'actuating member. and means for iilling said actuating member with fluid and for acting upon said member hydraullcally to cause the same to change its shape and volume, and to move the compression members to act upon the pumping member to aange its shape and volume, the actuating member and th'e pumping member each being capable of returning of itself to its original form when free to do so.l

17. In a hydraulically driven pump, a hollow actuating tubular member and a hollow tubular pumping member, within said actuating member.

, inlet and outlet means for said pumping member, if. compression parts positioned within said aotuat'- ing member to be moved by movement of said ac i: tuating member and to move said pumping tube. and means for filling said actuating member with "1 fluid and for acting upon said member hydraulically to cause the same to change its shape and volume, and to move the compression members to act upon the pumping membei to change its shape and volume.

18. In a hydraulically driven pump, ahollow actuating tubular member and a hollow tubular pumping member, within said actuating member, 5 linlet and outlet means for said pumping member, compression parts positionedto be moved by movement of said actuating member and to move said pumping tube, said parts being within the actuating'member. and means for filling said acl0 tuating member with iluid and for acting upon said member hydraulically to cause the same to change its shape and volume. and to move the compression members to act upon the pumping member to change its shape and volume.

19. In a differential hydraulically driven pump,

a hollow actuating tubular member and a hollow tubular pumping member within said actuating member, inlet and outlet means for said pumping member, compression parts positioned to be moved by movement oi' said actuating member and to move said pumping tube, said parts being within the actuating member, and means for filling said actuating member with iiuid and for acting upon said member hydraulically to cause the same to change its shape and volume, and to move the compression members to act upon the pump- 'ing member to change its shape and volume.

20. In a diiierential hydraulically driven pump, a hollow actuating tubular member and a hollow tubular pumping member, within said actuating member, inlet and outlet means for said pumping member, compression parts positioned to be moved by movement of said actuating member and to move said pumping tube, said parts being within the actuating member, and means for filling said actuating member with fluid and for acting upon said member hydraulically to cause the same to change its shape and volume, and to move the compression members to act upon the 'pumping member to change its shape and volume,

the actuating member andthe pumping member each being capable of returning of itself to its original form when free to do so. a

21. In a fuel supplying system, a hydraulically actuated pump, comprising two tubular members, one within the other, means for supplying fluid under pressure to the space within the outer tube and means for creating pressure upon such duid to distort the outer tube and thereby to compress the inner tube. said pressure 'creating means comprising a pump having a housing, a plurality of passages within the housing, a lpump chamber and a piston lying within the chamber.' there being passages within the piston, all of said passages forming a closed system, whereby as the piston is reciprocated the fluid within the closed system is compressed.

22. In a fuel supplying system, a hydraulically actuated pump. comprising two tubular members, one within the other, means for supplying iluid under pressure to the space within the outer tube and meansi'or creating pressure upon such iiuid to' distort the outer tube and thereby to compress 65 the inner tube, said pressure creating means comprising a pump -having a housing, a plurality of passages -within the housing, a pump chamber and a piston lying' within the chamber, there being passages within the piston, all of said passages forming a `closed system, whereby as the piston is reciprocated the fluid within the closed system is compressed, and automatic means connecting the said closed circuit with a iluid supply, whereby a substantially constant quantity of duid is automatically maintained within the closed system.

23. In a mechanism for creating intermittent high pressure in a liquid system, a vessel adapted to contain the liquid to be acted upon, means for applying pressure to the liquid within the vessel. said means including a flexible metallic member and a co-operating rigid driving member bearing against and adapted to act directly upon said ilexible metallic member, the flexible member positioned to exert pressure upon the liquid containing vessel and hydraulic means for actuating said metallic flexible member, said flexible member and said rigid driving member being dimensioned and proportioned as to weight and controlled as to range of movement such that the inertia force of said members when moving at a speed of more than 2000 strokes per minute is less than the transmitted force required to produce 5000 pounds per square inch pressure upon the liquid.

24. In a mechanism for creating intermittent high pressure in a liquid system. a vessel adapted to contain the liquid to be acted upon, means for applying pressure to the liquid within the vessel, said means including a ilexible member and a cooperating mechanical driving means in contact with said iiexible member, the flexible member positioned to exert pressure upon the liquid contained within the vessel, and hydraulic means for actuating said flexible member. said flexible member and cooperating mechanical driving means being dimensioned and proportioned as to weight and controlled as to range of movement so that the inertia force of said members when moving at a speed oi' more than one thousand strokes per minute, is less than the transmitted force required to produce one thousand pounds per square inch upon the liquid.

25. In a mechanism for creating intermittent high pressure in a liquid system, a vessel adapted to contain the liquid to be acted upon, means for applying pressure to the liquid within the vessel, said means including a tiexible member and a cooperating mechanical dr. Jing member bearing against and adapted to operate directly upon said ilexible member, the flexible member positioned 1 exert pressure upon the liquid contained in tl vessel, and hydraulic means for actuating sa. flexible member, the flexible member and sai mechanical driving member being dimension: and proportioned as to weight and controlled x to range of movement so that the inertia force said members when moving at speeds of moi than one thousand strokes per minute is less tha the transmitted i'orce required to produce fh hundred pounds per square inch pressure upo the liquid.

28. In a liquid fuel pump. a metallic pumpin chamber of variable volumetric capacity and ir cluding a deformable wall, a pressure chamb( overlying said deformable wall, a pressure mediui within said chamber, and means for creatin pulsations in said medium, rigid means for tran: mitting said pulsations to said deformable wal said deformable wall and said rigid means bein dimensioned and proportioned as to weight an controlled as, to range oi' movement such that th force necessary to overcome inertia thereof is le: than the force necessary to overcome the hydro static load on said wall member.

27. In a high pressure liquid fuel pump, pumping chamber oi' variable volumetric capacit and including a relatively movable wall membel a pressure chamber overlying said wall membe and including a relatively movable wall, a pres sure medium within said pressure chamber, righ motion transmission means operatively interpose between the movable wall of the pressure cham ber and the movable wall of the pumping cham ber, means for creating in said pressure chambe alternate pulsations of high and low pressure t cause movement o! said wall members to periodi cally vary the volumetric capacity ot the pump ing chamber, said wall members and interpose( rigid member being constrained to a range o: movement with respect to their relative weightsuch that the force necessary to Aovercome thi combined inertia ofsaid elements is less than thi force necessary to overcome the hydrostatic loa( on the movable wall of the pump.

PHILIP LANE SCO'II. 

